Sesto Senso 3 - Robotic focuser for Schmidt-Cassegrain

SESTO SENSO 3 SC - Robotic focusing motor for Schmidt-Cassegrain telescopes

SESTO SENSO 3 SC is the most advanced robotic focusing motor ever designed by PrimaLuceLab for Schmidt-Cassegrain (SC) and similar, equipped with an internal focusing system. It is compatible with Celestron Schmidt-Cassegrain (6″ to 14″), EdgeHD (8″, 11″, 14″), RASA (8″ to 14″) and the SkyWatcher MAK180. Inspired by the success of previous generations, it integrates even more cutting-edge technologies in a compact, robust housing that houses all the electronics and motorization.

Key features

• All-in-one compact chassis - Designed for SC telescopes with internal focusing, without the need for complex external adapters.
• Integrated encoder - Precise position tracking and manual movement possible without loss of reference, with automatic recovery function.
• Direct Pulley Clamp (DPC) - Backlash-free belt system for smooth motorized focusing and manual control at all times.
• High-resolution engine - Capable of over 2 million steps for extremely precise control of internal mirrors.
• USB-C connectivity - Fast, reliable connection to computers via standard cable.
• Integrated Wi-Fi - Wireless control via smartphone or tablet with Virtual HandPad integrated.
• PLAY compatibility - Complete focus control with autofocus and thermal compensation.
• ASCOM compatibility - Seamless integration with NINA, SGP, MaxIm DL and other astrophotography software.
• Dedicated ARCO port - Direct connection to ARCO rotator without additional cable.
• DARK Mode - Variable-intensity LEDs can be completely deactivated to preserve night vision.
• GHOST Mode - USB cable-free operation when connected to a computer EAGLE.
• Temperature sensor (optional) - Automatic focus compensation according to temperature variation.
• Weight - 440 g (1.0 lb), made entirely in Italy.

Compact design and full connectivity

Visit SESTO SENSO 3 SC integrates all electronics in a single, elegant housing, with side ports for easy access. It features brightness-adjustable LED indicators, a USB-C for connection to a computer or EAGLE, a port ARCO for rotator, a 12V power supply (5.5/2.5 mm connector, positive center) and a temperature probe port. The package offers minimal wiring and rapid installation, ideal for nomadic setups or remote observatories.

Simplified installation with Direct Pulley Clamp (DPC)

The new system Direct Pulley Clamp is specifically designed for telescopes with internally moving mirrors, such as Celestron SC, EdgeHD, RASA and SkyWatcher's MAK180. Based on a backlash-free belt drive, it guarantees smooth, precise motorized focusing, while allowing manual adjustment at any time. The internal encoder retains the exact position of the mirror, even after manual adjustment. Thanks to the included adapters, the SESTO SENSO 3 SC fits the following models:

• Celestron Schmidt-Cassegrain from 6″ to 14″
• Celestron EdgeHD 8″, 11″, 14″ (except EdgeHD 9.25″)
• Celestron RASA 8″, 11″, 14″
• SkyWatcher MAK180PRO

Integrated encoder and automatic calibration

The integrated encoder constantly monitors the motor shaft position, even during manual adjustments. The SESTO SENSO 3 SC also features a automatic calibration mode which detects the minimum and maximum positions of the internal focusing system, enabling fully remote configuration - a major asset for automated observatories.

The function Automatic Position Recovery automatically restores the previous position if manual movement is detected. A customizable delay (from 0 to 20 seconds) can be set before the position is restored.

Modern, reliable connectivity

Its port USB-C offers a robust, reversible connection, ideal for night-time observation conditions. This modern interface prevents accidental disconnections and integrates easily into existing IT systems. Integrated Wi-Fi allows total control without a computer, via smartphone or tablet.

Extended software compatibility

The SESTO SENSO 3 SC is fully compatible with the SESTO SENSO software. PLAY from PrimaLuceLab, offering intuitive motor control, autofocus and automatic thermal compensation functions. It also works with all astrophotography software supporting the ASCOM (NINA, SGP, MaxIm DL, etc.), guaranteeing perfect integration in any environment.

Wireless control via Wi-Fi

The integrated Wi-Fi module creates its own network, allowing direct control from a smartphone or tablet via the Virtual HandPad browser-accessible. You can adjust focus, save favorite positions and control the system without cables. Wi-Fi remains active even when connected via USB, for flexible dual control.

Direct integration with ARCO rotator

Thanks to its dedicated port, the SESTO SENSO 3 SC connects directly to the ARCO rotator, which allows you to remotely rotate the camera for precise framing, or apply a field derotation for long exposures with an alt-azimuth mount. A single cable is all you need for power and data transfer, greatly simplifying wiring.

DARK Mode and LED management

The integrated status LEDs are fully adjustable. At DARK Mode, They can be reduced or deactivated completely, preserving night vision. When used with a EAGLE, dark mode is automatically activated at the start of an imaging sequence.

GHOST Mode and firmware updates

In GHOST, The SESTO SENSO 3 SC can operate without a USB cable when connected to an EAGLE computer. This mode also acts as a backup link: if the USB cable is disconnected, control via EAGLE remains active. Firmware updates can be easily installed via the PLAY software to benefit from the latest enhancements.

Temperature sensor and automatic compensation

The dedicated port for the optional temperature sensor enables automatic focus compensation according to temperature variations during the night. After calibration in the PLAY software, the system automatically adjusts focus, guaranteeing stable results even on fast instruments (f/3 and higher).

Technical data

Box contents

• SESTO SENSO 3 SC
• Adapters and mounting hardware
• USB-C to USB-A cable
• 12 V power cable (cigarette-lighter plug)
• Hexagonal assembly wrenches
• Quick installation guide

The SESTO SENSO 3 SC pushes the limits of robotic focusing for Schmidt-Cassegrain telescopes, offering micrometric precision, extensive software compatibility and seamless integration into modern imaging systems.